Manufacture or treatment of materials made of or containing cellulose esters or ethers



Patented Aug. 3, 1937 MANUFACTURE OR TREATMENT OF MATE- RIALS MADE F 01% CONTAINING CELLU- LQSE ESTERS OR ETHERS George Holland Ellis, Spendon, near Derby, England, assignor to Celanese Corporation of America, a corporation of Delaware No Drawing. Original application December 24,

1929, Serial No. 416,29 plication ()ctober 16,

2. Divided and this ap- 1934, Serial No. 748,532.

lln Great Britain January 5, 1929 14 Claims.

This invention relates to the treatment and also to the manufacture. of artificial silk and other filaments or products and to the treatment of yarns, fabrics or other materials made 5 of or containing cellulose esters or ethers, and is a divisional of my U. S. application S. No. 416,292 filed December 24, 1929.

It is well known that commercial cellulose acetate artificial silk becomes delustered when treated with hot or boiling aqueous liquids or with moist steam. This property is particularly noticeable with dry-spun artificial silks, but it is also observable in wet-spun fibres. This property of becoming delustered when subjected to the action of hot aqueous media or steam is often a drawback in the subsequent processing of the artificial silk.

The object of the present invention is to produce lustrous artificial material in filament, thread, yarn or fabric form which will not delustre when subjected to the action of hot aqueous liquids or moist steam or in which the extent to which delustering occurs with such media is considerably reduced.

I have found that non-delusterable products made of or containing cellulose acetate (i. e. 5 products in which the cellulose acetate portion resists or substantially resists the delustering action of hot aqueous liquids or moist steam) 30 may be produced by incorporating in the materials during, continuously with or after their production, a solvent or gelling agent for the cellulose acetate, and by subjecting the complex thus formed to a steaming operation with dry 35 steam. Solvents and gelling agents are referred to in the following description and claims under the single term solvents but it is to be clearly understood that this term includes not only true solvents for the cellulose derivatives but substances which exert a gelling action on the cellulose derivatives.

The solvent may be any substance capableof dissolving or swelling the cellulose acetate. Preferably, the substances employed are nonvolatile under the conditions of the subsequent treatment. Such substances are, for example, resorcinol, hydroquinone, cresols, diacetin, paratoluene-sulphonamide, and the isomeric xylene 50 sulphonamides and their methyl and ethyl derivatives, diethyl-tartrate, phthalimide and mixtures of such bodies. The invention is not, however, limited to such high boiling solvents, and results of considerable value may be obtained 55 with agents of much greater volatility, for exglycol ethers or acetic acid.

ample, phenol, ethyl lactate, diacetone alcohol,

As stated above, the solvent may be incorporated in the cellulose acetate product during, continuously with or after its production. For example, a product consisting of or containing cellulose acetate artificial silk may be immersed in a solvent or a solution or dispersion of the same, or a solvent may be applied to the fibre by mechanical means, for example by treatment with a solution or dispersion thereof in a padding mangle. Alternatively, the solvent may be dissolved in or form part of the spinning solution employed for the manufacture of the artificial silk. When the solvent is introduced into the spinning solution itself, it should be of sufiiciently low vapourpressure to remain in the product to a substantial extent after the spinning operation is completed.

In the case of wet-spun artificial products, the solvent may be incorporated in the products continuously with or in the course of their production by the methods described in prior U. S. application S. No. 402,785 filed October 26, 1929, i. e. by employing a solvent in the precipitating bath in sufiicient concentration to be carried forward out of the bath by the formed products, or secondly by incorporating in the spinning so-- lution itself a solvent less volatile than the nonsolvent media in the precipitating bath andin sufiicient quantity to enable it to be carried out of the precipitating bath by the products, or thirdly by leading the products directly from the precipitating bath into a suitable bath containing the desired solvent.

As indicated above, the actual rendering of the artificial materials non-delusterable is efiected by a treatment with dry steam. The time of steaming will depend to some extent upon the nature of the cellulose acetate artificial material under treatment and upon the particular solvent employed, and may also depend upon the actual temperature of the steam or the temperature to which the artificial material is raised during the steaming. Temperatures of about 100 C. appear to be very efficacious, but temperatures considerably higher, obtained for instance by means of steam under pressure, may The duration of the steaming should not in general be extended beyond that be employed.

necessary to achieve the desired results, though it is found that the steaming may be prolonged considerably above the optimum period without qualities of the substantially impairing the products.

As indicated above, the duration of the steaming depends upon a number of factors, such as temperature, nature of reagents, etc. If it is. sufliciently short, the steaming may be carried out continuously with the production of the artificial filaments or products. For example, dryspun artificial filaments, after leaving the spinning cells or chambers, may be caused to pass through a chamber where they are subjected for the necessary time to the action of dry steam. In conducting such continuous operations, the solvent may be incorporated in the spinning solution itself or may be applied to the filaments or other products during the course of their travel through the spinning cells or outside the spinning cells, for instance by the various methods described in prior U. S. application S. No. 393,287 filed September 17, 1929.

Again, wet-spun products may be treated according to the present invention continuously with their production. Thus, for example -fila'- ments issuing from the precipitating baths or after treatment baths described in prior U. S. Patent application S; No. 402,785 may be carried, with or without intermediate drying, into suitable chambers or other apparatus for efieoting the steaming.

By applying a stretch to the materials either before or during treatment, and particularly by stretching beyond the elastic limit, the modification of their properties may be materially assisted. Moreover, by applying a stretch, the temperature of the steaming may be reduced to below or considerably below the indications given above. Such stretch may, for example, be ap plied immediately before or during the early part or the whole of the steaming.

The various processes described above are, of course, applicable to the treatment of cellulose acetate filaments or threads of any type, for example fiat or ribbon-like filaments, semi-round and round filaments and the so-called hollow,

tubular or voluminous filaments or threads containing the same. The products treated may be non-.delustered products, e. g. normal lustrous products or products which have been spun in a lustreless condition or so as to have only a low lustre. If it is desired, however, to carry out the treatment of cellulose acetate materials of reduced lustre, such condition of low lustre. being due to a treatment of lustrous materials with moist steam or hot aqueous liquids, the materials should first be brought to a lustrous condition. This lustring may also be effected by incorporating with the materials a solvent for the cellulose acetate and treating the materials with dry steam. Thus, the lustring of such low lustre materials and the rendering of such materials resistant to delustring by the action of hot aqueous.

media may be carried out as a continuous process, lustring taking place before the modification of the properties rendering the materials nondelusterable. It will thus be appreciated that the degree of lustre of the materials treated according to this invention is not necessarily the same as the degree of lustre of the initial materials and, moreover, even the cross-section of the filaments may be altered by the treatment characteristic of this invention. The processes of the invention are further applicable to the treatment of fabrics or other products made of or containing cellulose acetate and to the treatment of filaments or threads, fabrics or other products made of or containing other cellulose esters, for example cellulose formate, propionate or butyrate, or made of or containing cellulose ethers, such as methyl cellulose, ethyl cellulose or benzyl cellulose or the corresponding condensation products of cellulose and glycols or other polyhydric alcohols and also to the treatment of mixed materials containing cellulose esters or ethers in association with other fibres, e. g. cotton, the cellulosic type of artificial silk, wool or silk.

The solvents introduced into the filaments, threads, yarns, fabrics or other products by the processes of the. invention may, if desired, be removed therefrom, for example by applying a subsequent washing operation.

The following examples illustrate the invention but are not to be considered as. limiting it in any way.

Example 1 Cellulose acetate yarn of normal lustre in hank form spun from an acetone solution of cellulose acetate containing 4% resorcinol on the weight of cellulose acetate is steamed for hour with dry steam at 5 lbs. above atmospheric pressure.

It now retains its lustre, even after 1 /2 hours boiling in a 1% soap solution, an untreated hank soaped simultaneously becoming quite delustered and Woolly.

Example 2 soaped simultaneously becoming quite delustered and woolly.

Example 3 Satin woven fabric of normal lustre made from cellulose acetate yarn is padded in a 20% solution of acetic acid, batched for 3 hours and hung for 15 minutes in a hot stove. It is now steamed in a cottage steamer for 1 hour with dry steam at 5 lbs. above atmospheric pressure,

and washed off thoroughly to remove residual,

acid. It now retains its lustre after boiling for 1 hours in a 1% soap solution, untreated fabric soaped simultaneously being much delustered.

Example 4 Cellulose acetate yarn of normal lustre in hank form is treated for 1 hours at 70 C. in a 1% aqueous solution of hydroquinone rendered faintly acidic with acetic acid. It is lifted, hydroextracted, and dried Without rinsing. It is now steamed for hour with dry steam at 5 lbs. above atmospheric pressure, washed off well, and dried.

It now retains its lustre after boiling for 1 hours in a 1% soap solution, untreated fabric being much delustered.

Example 5 Cellulose acetate knit fabric of normal lustre is treated in. a 30:1 bath of a 1% aqueous solution of p.toluene-sulphonamide for 2 hours at C. It is now washed off lightly, dried, and steamed for 45 minutes with dry steam at 5 lbs. above atmospheric pressure.

It now retains its lustre after boiling for 2 'hours in 1% soap solution, untreated fabric soaped simultaneously being much delustered.

What I claim and desire to secure by Letters Patent is:-

1. Process for the manufacture of artificial materials of increased resistance to the delustring action of hot aqueous media, comprising subjecting non-delustred artificial filaments, threads, yarns and the like having a basis of an organic derivative of cellulose and containing a solvent for the organic derivative of cellulose, and fabrics and similar materials containing such filaments and the like, to treatment with dry steam and continuing such treatment until the resistance of the materials to the delustring action of hot aqueous media is increased.

2. Process for the manufacture of artificial materials of increased resistance to the delustring action of hot aqueous media, compris ing subjecting lustrous artificial filaments, threads, yarns and the like having a basis of cellulose acetate and containing a solvent for the cellulose acetate, and fabrics and similar materials containing such filaments and the like, to treatment with dry steam and continuing such treatment until the resistance of the materials to the delustring action of hot aqueous media is increased.

3. Process for the manufacture of artificial materials of permanently increased resistance to the delustring action of hot aqueous media, comprising subjecting non-delustred artificial filaments, threads, yarns and the like having a basis of an organic derivative of cellulose and containing a solvent for the organic derivative of cellulose, and fabrics and similar materials containing such filaments and the like, to treatment with dry steam at a temperature approximately equal to the boiling point of Water under the pressure conditions prevailing, and continuing such treatment until the resistance of the materials to the delustring action of hot aqueous media is permanently increased.

4:. Process for the manufacture of artificial materials of permanently increased resistance to the delustring action of hot aqueous media, comprising subjecting non-delustred artificial filaments, threads, yarns and the like having a basis of an organic derivative of cellulose and containing a solvent for the organic derivative of cellulose, and fabrics and similar materials containing such filaments and the like, to treatment with dry steam and continuing such treatment until the resistance of the materials to the delustring action of hot aqueous media is permanently increased, the solvent contained in the materials being substantially non-volatile under the conditions of the steam treatment.

5. Process for the manufacture of artificial materials of permanently increased resistance to the delustring action of hot aqueous media, comprising subjecting lustrous artificial filaments, threads, yarns and the like having a ,basis of cellulose acetate and containing a solvent for the cellulose acetate, and fabrics and similar materials containing such filaments and the like, to treatment with dry steam at a temperature slightly above the boiling point of Water under the pressure conditions prevailing and continuing such treatment until the resistance of the materials to the delustring action of hot aqueous media is permanently increased, the solvent contained in the artificial filaments and the like being substantially non-volatile under the conditions of the steam treatment.

the materials to the delustring action of hot aqueous media is permanently increased.

7. Process for the manufacture of artificial materials of permanently increased resistance to the delustring action of hot aqueous'media, comprising subjecting lustrous artificial filaments, threads, yarns and the like having a basis of cellulose acetate and containing a solvent for. the

cellulose acetate, and fabrics and similar materials containing such filaments and the like, to treatment with dry steam under a pressure of about five pounds per square inch above atmosphe ic pressure and continuing such treatment until the resistance of the materials to the delustring action of hot aqueous media is permanently increased, the solvent contained in the artificial filaments and the like being substantially non-volatile under the conditions of the steam treatment.

8. Process for the manufacture of artificial materials of permanently increased resistance to the delustring action of hot aqueous media, comprising subjecting lustrous artificial filaments, threads, yarns and the like having a basis of cellulose acetate and containing a solvent for the cellulose acetate, and fabrics and similar materials containing such filaments and the like, to treatment with dry steam at a pressure of about five pounds per square inch above atmospheric pressure for at least hour and continuing such treatment until the resistance of the materials to the delustring action of hot aqueous media is permanently increased.

9. Process for the manufacture of artificial materials of permanently increased resistance to the delustring action of hot aqueous media, comprising subjecting non-delustred artificial filaments, threads, yarns and the like having a basis of an organic derivative of cellulose and containing solvents for the organic derivative of cellulose, to treatment with dry steam and to a stretching operation, the treatment With dry steam being continued until the resistance of the materials to the delustring action of hot aqueous media is permanently increased.

10. Process for the manufacture of artificial materials of permanently increased resistance to the delustring action of hot aqueous media, comprising subjecting lustrous artificial filaments, threads, yarns and the like having a basis of cellulose acetate and containing a solvent for the celulose acetate, to a stretching operation and to a treatment with dry steam at a temperature slightly above the boiling point of water under the pressure conditions prevailing, and continuing the treatment with dry steam until the resistance of the materials to the delustring action of hot aqueous media is permanently increased, the solvent for the cellulose acetate contained in the materials being substantially non-volatile under the conditions of the steam treatment.

11. Process for the manufacture of artificial materials of permanently increased resistance to the delustringaction of hot aqueous media, com-a prising as a continuous operation producing lustrous artificial filaments, threads, yarns and the like having a basis of an organic derivative of cellulose by a spinning process such that the materialscontain a solvent for the organic derivative of cellulose, subjecting such filaments and the like to treatment with dry steam and continuing such treatment until the resistance of the materials to the delustring action of hot aqueous media is permanently increased.

12; Process for the manufacture of materials of permanentlyincreased resistance to the delustring action of hot aqueous media, comprising subjecting artificial filaments, threads, yarns, fabrics and the like which contain an organic derivative of cellulose and which have been delustred by the action of hot aqueous media, to treatment with'dry steam in the presence of a solvent for the organic derivative 'of cellulose for a period substantially in excess of that neces sary to restore their lustre.

13. Process for the manufacture of artificial materials of permanently increased resistance to the delustring action of hot aqueous media, comprising relustring artificial filaments, threads, yarns, fabrics and the like containing an orgarlic derivative of cellulose which have been idelustred by the action of hot aqueous media, by treating such materials with dry steam in the presence of a solvent for. the organic derivative of cellulose until the lustre of the materials is restored and then continuing the treatment of the materials until the resistance of the materials to the delustring action of hot aqueous media is permanently increased.

14. Process for the manufacture of artificial materials of increased resistance to the delustring action of hot aqueous media, comprising relustring artificial filaments, threads, yarns, fabrics and the like containing cellulose acetate which have been delustred by the action of hot aqueous media, by treating such materials with dry steam at a temperature slightly above the boiling point of water under the pressure conditions prevailing, in the presence of a solvent for the cellulose acetate which is non-volatile under the conditions of the steam treatment, and

continuing the steam treatment of such materials after the original lustre of the materials has been restored until the resistance of the materials to the delustring action of hot aqueous media is permanently increased.

GEORGE HOLLAND ELLIS. 

